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ARGH!  ZMA crackling noise issue. (Read 33204 times)
HockessinKid
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ARGH!  ZMA crackling noise issue.
03/18/17 at 14:32:11
 
Hey Guys,

I have an email into Steve to resolve an issue with my new ZMA amp.  After setting up the ZMA and CSP3 preamp I have a pretty loud, steady crackling noise in both speakers with any volume set past about 15-20%.  It was a bit unnerving hearing this after powering up the amp.  All four bias meters start moving around as well when I push the volume up.

I am hoping this is just a bad set of power tubes, as I'm dreading the thought of having to ship the beast back to Steve for repairs. Cry

Any insights/thoughts from you ZMA owners out there in Decware land?

HK
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Lon
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Re: ARGH!  ZMA crackling noise issue.
Reply #1 - 03/18/17 at 14:35:33
 
I don't have a ZMA nor any particular insight into this problem. . . but I would try to reach Steve by phone. I don't know about weekend hours, but in the past many have noted that reaching Steve by phone (a guy who likes to talk on the phone!) is quicker and easier than getting a quick email response. And I think you'll want this corrected as soon as possible and Steve is THE best "first responder."
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #2 - 03/18/17 at 14:59:40
 
Thanks Lon, very good suggestion.  Just called and left a voice mail for Steve in case he is in during the weekend.  He does like to talk on the phone.

HK
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Archie
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Re: ARGH!  ZMA crackling noise issue.
Reply #3 - 03/18/17 at 19:07:50
 
Does it happen without the CSP3 as well?  That it comes out of both channels is odd if it's a ZMA issue since the two channels are separate -- two mono blocks in one chassis with only the IEC and volume pot in common.  Could be a volume pot or CSP3 issue?
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #4 - 03/18/17 at 19:40:45
 
I will check on this Archie by running my CDP directly to the ZMA.  Sent Steve a video w/ sound to he can diagnose the problem and get back to me.  What service - on a weekend no less.

HK
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Archie
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Re: ARGH!  ZMA crackling noise issue.
Reply #5 - 03/18/17 at 20:58:34
 
Yeah, you don't have to worry about Steve dropping the ball.  I'm hoping it's just a CSP3 tube.  Everything is tubed correctly?  I remember a couple years back someone had a problem with a new ZP3 and it turned out he switched up the tubes.  Great if it's that simple!

I've had some crackling from my ZMA input tubes but not what you describe.  In my case the tubes were at fault.
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #6 - 03/18/17 at 21:16:36
 
Archie, ran the CDP directly.  Got a very loud buzzing noise, different sounding from crackling sound (almost sounds like popcorn popping loudly) with the CSP3 hooked up.  All the tubes are properly placed in the right position, I triple checked them before turning on the preamp and amp.

After Steve reviews the video I sent him, I'll sure to get a call.  I still have my 2 watt Zen amp and Eastern Electric preamp if something needs to go back.  At least I'll have music.

BTW, even at relatively low volumes I can tell this amp is going to be something very special when the tubes and caps burn in fully.

HK
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Archie
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Re: ARGH!  ZMA crackling noise issue.
Reply #7 - 03/18/17 at 21:49:26
 
I take it you don't have a different source to try?  That the sound changed without the CSP3 makes me question the source.  But of course, Steve is your best shot at figuring this out.
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #8 - 03/19/17 at 00:53:23
 
Update: It's definitely the amp or amp tubes.  I put my little Decware Zen back into my system with the CSP3 preamp. Everything was quiet as a church mouse.  The CDP and turntable sounded great, they are not the problem.

HK  

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Lon
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Re: ARGH!  ZMA crackling noise issue.
Reply #9 - 03/19/17 at 01:29:48
 
I hope it gets sorted really soon! Must be frustrating. . .luckily you have that backup Zen amp!
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alper_yilmaz
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Re: ARGH!  ZMA crackling noise issue.
Reply #10 - 03/20/17 at 19:15:29
 
Have you tried swapping the input tubes?  On my Copland push-pull, I had a similar issue few months ago.  Even when the volume was turned down all the way to zero, it made this loud crackling noise on one of the channels.  I also thought it was one of the output tubes, but it turned out to be one of the 12BH7's...
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #11 - 03/20/17 at 21:36:44
 
I sent a video of the noise problem to Steve.  He's never heard anything like it (electronic corn popping) in the ZMA, especially since the noise is in both channels.  Having ruled out the preamp and amp tubes as the problem, the ZMA is heading back to the shop tomorrow for a once over and necessary repairs.  BTW, Decware makes returns for new product repairs very easy.

Thankfully, I have my trusty old Zen amp back in my main system for listening until I get the ZMA back.  I told Steve that even with the noise it was clear this is a VERY SPECIAL amp.  

HK
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JD
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Re: ARGH!  ZMA crackling noise issue.
Reply #12 - 03/21/17 at 12:14:03
 
HockessinKid,

Way to keep a level head about the whole thing, impressive. I know the wait will be worth it.

JD
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #13 - 03/21/17 at 15:34:36
 
JD,

Having dealt with Steve and his Decware team before on upgrading my Zen amp, I know that they work extremely hard to deliver exceptionally high quality audio products for very reasonable prices.  Even with careful QC, sometimes things just go wrong.  

It was a bit unnerving initially listening to the crackling/popping sound of the new amp after waiting some 14 weeks on the build. My heart did sink a bit, it was frustrating.

With that said, hearing the capability of this amp at low volume levels w/out the noise was simply captivating.  So, I give kudo's to Steve and Sarah for arranging a quick ship back to the shop and know that the amp will be gone over with a fine tooth comb to fix the issue.  I think that's all any reasonable person can/should expect from an audio equipment manufacturer.  As the wise man once said, "sh*t happens", it's the follow-up that matters.

HK
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stone_of_tone
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Re: ARGH!  ZMA crackling noise issue.
Reply #14 - 03/22/17 at 16:29:47
 
Steve and Sarah were as good as it can get with my repair. Heck, it was serendipitous for me. My ZMA came back better than ever (Steve gave me backlit meters, volume pot and new 001 serial number sticker and tweaks). It just needed beefier resistors for the meter's and a three year check up. Mine was the first one shipped, back in mid January, 2014.

Yes, you noticed at low volume how good this Amp is................ . I swear mine did come back to me even better. The check up/adjustments did her good.

Enjoy the journey.  My journey continues with NOS Platinum input and inverter tube rolling. I recently had a Pre in and decided to send back. I love my ZMA sans Pre. CSP3 is awesome though..... .  I had one for 27 months with my ZMA.

Hope it's back soon.   Enjoy.
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #15 - 03/22/17 at 23:10:59
 
Yes SOT, it's the ZMA heading back UPS tomorrow, hopefully for a quick turnaround on repairs. It's a real pleasure dealing with Steve and Sarah, true professionals.  Steve wants to get it rights, kudos to him.

HK
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Ace-Tone
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Re: ARGH!  ZMA crackling noise issue.
Reply #16 - 03/31/17 at 18:48:14
 
HK,  So are things good now?
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #17 - 04/01/17 at 15:03:27
 
Acetone,

Steve tested the amp and couldn't find any problems.  He suspects it may be cable related. From Steve, "if a cable is letting in RF or has a weak ground it's performance will vary relative to the amount of gain the amplifier has.  Since the ZMA has more gain and power than the Zen amp, it could be picking up an oscillation through the cables that the smaller amp doesn't see."  

Steve offered to walk me through the set up and isolate the problem when I get the amp back in my system.  I am currently using Reality Cable IC's which are un-shielded, so we'll see if the issue lies there.  Anyway, my ZMA is currently in transit back home, hopefully by Tuesday we bring this situation to a conclusion.

HK
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mark58
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Re: ARGH!  ZMA crackling noise issue.
Reply #18 - 04/01/17 at 15:56:03
 
Well Kid, too bad you had to send it in but a cable problem is easily fixed...upgrade your cables  :)

A ZMA deserves some great ones!

My suggestion...start a thread to ask what other ZMA owners use and like. Mark.

PS...Lon and I both use Voodoo interconnects with our Torii's...his top of the line...mine the ones he didn't want and sold...
There may be a couple others who use them on the Forum.  But be warned, they are very expensive even used and they don't come up for resale often.  Believe me, I have been looking since I got the first pairs.
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The motions of his spirit are dull as night and his affections dark as Hell. Let no such man be trusted." William Shakespeare
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Lon
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Re: ARGH!  ZMA crackling noise issue.
Reply #19 - 04/02/17 at 03:14:02
 
I don't have a ZMA but use a Torii Mk III and have gone through some cables to find ones that allow my amp to be all it can be.

I used Reality cables at one time between my DAC and amp, they're nice. I replaced them with Cryoset.com Version 2 interconnects that I preferred, a bit more full-bodied and a touch warmer. I still have these in storage but I eventually moved to VooDoo Cable interconnects as Mark notes, first Evolution, then Ultralinear and then to Stradivarius and Stradivarius Cremona edition. This is a very good line of cables, using both the Oho copper and sliver wire (not silver-plated copper) for conductors, well-shielded, and cryo treated. As I improved my front end sources these let me really hear what they were dishing out, and I've never had any other noise or sound issues.

It's possible just re-routing present cables may prevent these issues. . . I once had a hum drove me nuts and pulled every cable off every component, payed attention to how they were put back in place with as much non-interference as possible, and the hum was gone. And stayed gone!
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #20 - 04/02/17 at 14:26:00
 
Thanks Lon.  I appreciate your suggestions and insights on cabling.  I will reroute cables to see if this eliminates the problems.  I currently try to keep my IC's perpendicular to my power cords, careful not to overlap them.  I also pulled my source equipment rack out a bit.  The wall immediately behind the rack has an encased, basement steel support pole.  With the IC's in close proximity, maybe the pole was acting as an antenna?

Oh well, I'll get it sorted out.

HK
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Lon
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Re: ARGH!  ZMA crackling noise issue.
Reply #21 - 04/03/17 at 15:55:12
 
That steel plate might be a culprit. Interested in hearing what you discover.

One other recommendation: Take Five Audio. I have their most expensive coaxial digital cable and it is outstanding. And I have their most expensive XLR cables going from my DirectStream DAC to the ZBIT and they are also outstanding. Both of these cable types use PCOCC copper and are cryo treated. Not cheap but not stratospherically priced and great performers.
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #22 - 04/04/17 at 21:24:35
 
My ZMA gremlins saga continues.  So, it looks like I have two issues.  First, unshielded IC's from source equipment to my CSP3 preamp are causing some noise.  This is easily remedied with some shielded IC's. Second, a continuous hum from the ZMA amp to my Omega speakers, this with no sources connected.

After trying a myriad of potential fixes for my ZMA amp hum (changed out input & power tubes, power cords, cheater plug, switched cabling, checked electrical outlet polarity, system swapping, etc.), Steve believes there is an intermittent problem with the amp.  It will be heading back to the bench in Peoria, IL for a second time.  If Steve can't repair it, he promised to build me a new one.

It's been frustrating to not find a solution.  The only saving grace is my little Zen amp keeps me in the music.  It may be a couple of weeks or so before I get repairs completed or a new ZMA back into my system.  Until then, happy listening everyone.

HK
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mark58
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Re: ARGH!  ZMA crackling noise issue.
Reply #23 - 04/04/17 at 21:27:04
 
Kid, how loud is the hum...I have some transformer hum with my Torii that isn't noticeable with Music playing.  
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The motions of his spirit are dull as night and his affections dark as Hell. Let no such man be trusted." William Shakespeare
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #24 - 04/04/17 at 21:59:54
 
Mark,

It's very loud and hum increases intensity with the volume.  

HK
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Re: ARGH!  ZMA crackling noise issue.
Reply #25 - 04/05/17 at 01:43:17
 
Bummer! Always good to have a back up Zen available.
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Re: ARGH!  ZMA crackling noise issue.
Reply #26 - 04/05/17 at 01:44:39
 
HK...I had a mysterious hum with my ZMA as well.  I recently moved my entire system and it's gone.  

I know I have a ton of noise pollution RFI where I live, because it is amplified by my guitar amps and other audio equipment (powered speakers).  

My hypothesis is that the crazy cable situation I had going on in a tight space behind the system wasn't helping.  I also have a SuperZen amp, and it was impervious.  Not sure exactly what was going on, but it was definitely amp dependent.

Can you bring your amp to a friends place to see if the problem still exists there?

Sounds like your issue is worse than mine, but I feel your pain...

Dave
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #27 - 04/05/17 at 10:47:32
 
Dave,

Took the amp to my sons place, installed it in his system and the loud hum still persists.  So it's heading back.

HK
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Re: ARGH!  ZMA crackling noise issue.
Reply #28 - 04/11/17 at 01:37:23
 

I am pleased to be able to say that I have found the problem with the amp and less pleased to admit I didn't find it during the original QC process and the second QC process when it came back. Turns out we omitted the bridging capacitor/resistor that connects the audio ground to earth ground. Just goes to show that when you're obsessed with finding something wrong with something it seldom occurs to you to look for what is not there.

Since the audio ground and earth ground are bridged together through the test equipment the missing parts would have non consequence during the QC process.  When these two missing parts are installed, I always check them to be sure they work correctly, but when they're not there and the amp still reads hum at -72.4dB...

This is a classic example of how I have learned literally everything I actually know. It's amazing how well memory works when large sums of money are involved.

Anyway, we'll get the amp back in the mail this week so you can finally start enjoying it.

Thanks,

Steve

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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #29 - 04/11/17 at 17:27:07
 
Thanks for your diligence Steve.  I look forward to getting the amp back in my system for some enjoyable listening!

HK
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Re: ARGH!  ZMA crackling noise issue.
Reply #30 - 04/26/17 at 19:49:24
 
Yay!  I have a quiet ZMA now.  Have just begun the burn in process -  5 hours on, 5 hours off for a few days.  Sounds great right out of the shipping crate.

HK
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Re: ARGH!  ZMA crackling noise issue.
Reply #31 - 04/27/17 at 03:40:02
 
Yes, I remember the ZMA sounded great right out of the pelican case. Detail was impressive.  And then it just gets better and better.
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VPI Classic w/ Ortofon 2M Black, ZP3; PS Audio DSD & PST; ZMA, Zenstyx; Bösendorfer VC-7
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Ace-Tone
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Re: ARGH!  ZMA crackling noise issue.
Reply #32 - 04/27/17 at 16:31:23
 
That's good news HKid....I can't imagine being without my Zen amp for weeks at a time. Enjoy!
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Steve Deckert
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Re: ARGH!  ZMA crackling noise issue.
Reply #33 - 06/05/17 at 20:07:41
 
Quote:
Yay!  I have a quiet ZMA now.  Have just begun the burn in process -  5 hours on, 5 hours off for a few days.  Sounds great right out of the shipping crate.

HK


You should be past most of the break in by now, care to comment on the final result?

Thanks,

Steve
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HockessinKid
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Re: ARGH!  ZMA crackling noise issue.
Reply #34 - 06/05/17 at 21:53:35
 
So the ZMA with stock tubes has sufficiently settled in and for the last couple of weeks I've been auditioning some of Dave Cahoon's (Zenwave Audio) IC's with my system.

Here are my impressions:  The ZMA is an exceptional, musically satisfying amplifier.  It is absolutely quiet in my system, has perfect tonality to my ears, and creates an insanely accurate 3D soundstage driving my Omega Super Alnico High Output speakers.  

The sound from my speakers really opened up when I replaced my Reality Cables with Zenwave's offerings (D3 & D4 interconnects and SMSG speaker cables).   I can just hear so deeply into the music now.  It appears that the ZMA benefits from the best cables you can throw into the mix.

It's difficult for me to put the sound characteristics of the Mystery amplifier into words.  But to me what best describes this amp is the immersive listening experience you'll enjoy with decent source equipment and speakers.  You simply get lost in the music.  And after all isn't that what this hobby journey is all about?

This amplifier was a early retirement gift to myself.  Having worked in the non-profit conservation arena throughout my career, I just count my blessings people like Steve Deckert make such wonderful audio products that most folks can afford.  Sonic nirvana awaits - thanks Steve.

HK
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Nottingham Interspace TT w/ Audio Technica AT-OC9XML cart & Modwright PH 9.0XT phono preamp OR MWI modded Cambridge CNX V2 > CSP3-25th A preamp > ZMA-25th A amp > PI Audio UberBUSS > Caintuck Audio Lii15 Magnum speakers > SDFB's > SRA & ZenWave cables
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Steve Deckert
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Re: ARGH!  ZMA crackling noise issue.
Reply #35 - 06/06/17 at 01:39:35
 
Thank-you for the followup, and thank-you for not giving up on us when things weren't going right!  

You are correct about cables...  I created the amplifier, have 1000's of hours with it and believe it or not, I heard it for the very first time just the other night... (check my post called Vinyl Orgasm in the Vinyl forum)

It just proves for the one millionth time, that you only hear your system rise to the limitations of the weakest component or cable.  Speakers and rooms themselves are considered components in the chain as well.

Anyway, we hope you enjoy the journey and please keep us posted as it unravels.

Thanks,

Steve
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Jeff of Arabica
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Re: ARGH!  ZMA crackling noise issue.
Reply #36 - 06/06/17 at 06:32:44
 
HK,
Glad to hear all worked out with the ZMA.  I knew it would. When you have a product predicated on quality built by a company with a genuine desire to serve the customer, there really is no other outcome - other than good.  

I have the exact same speaker & amp combo as you and having about a month on my new Omega SAHO's with the ZMA, I couldn't be more pleased.  I still have and use my Monoliths and they are phenomenal with the ZMA as well.  They are serving a new purpose now and fulfilling it well!  The ZMA is magical.  And with the right combination of speakers and allied components, I can't believe that I don't have the best that can be - at least for my preferences.  Real, musical, dynamic... are the best three words I can come up with.  

I recently added a ZSB switch box to allow me to go direct from source to ZMA.  I previously ran everything through my Decware Ultra pre-amp but always wondered what it would be like to go direct.  I am very pleased so far.  But in all honesty, I have not truly decided which I prefer.  Now I tubed the hell out of both, and did so to achieve a synergy that I believe is the very reason why I am not quite certain - yet- which I prefer.  I purchased (8) Reflektor "Holy Grail" '75 input tubes.  I put a matched quad in the ZMA.  I then put a matched pair on the "mains" pre-amp section of the Ultra and another matched pair on the "mixed" section of the Ultra since the mains are routed through the mixed sections tubes to add some additional "tube love" as Steve puts it for 2-channel listening.  Those eight 1975 Reflektors, working in harmony between my Ultra and ZMA, is something special.  I get the benefit of riding the gain, but with a set of tubes that are perfectly matched between the Ultra and ZMA.  Had I not tube rolled in this manner, I am not sure my results would have been what they are.  I also put some Gold Lion KT66's in the ZMA and a PSVANE 275B in the Ultra.  Beautiful sound.  

I am actually hoping that I will like the direct to ZMA at least as much as the Ultra in between, since it is a simpler path and one that doesn't require the powering up of an ungodly amount of tubes just for 2-channel listening.  
The ZMA is the "bees knees" (and I have a Torii MK IV and had a Torii Jr.)  and I am so pleased with the sound the ZMA is able to create with Loius' SAHO's.  For now... I am perfectly content.  

As far as the "heavy lifting," the ZMA/Omega combo is a match made in heaven.  Now I can fine tune as needed with IC's, source components, etc.  As you know - or soon will know - you are never really "there."  It is always inspiring to once "be there."  But, it is that journey that we all enjoy so much.  So, I hope I never quite get there because the pursuit is too much fun. I am ok with 99.99%.  That 0.01% is enough to keep me motivated to continue on Smiley

Enjoy your most wonderful speaker & amp combination!
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Jadis JA-30 MKII//ZMA//Zen Ultra//Waversa DAC3//ModWright Oppo UDP-205//EMM Labs DS-EQ1//DS Audio DS-003//FFYX T1803 TT//SonoruS Reel-to-Reel & tube playback preamp//Pipedreams Reference 21 Speakers
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JD
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Re: ARGH!  ZMA crackling noise issue.
Reply #37 - 06/06/17 at 12:20:15
 
Fantastic how well the ZMA is performing with the Omega SAHO's for you guys. I have been breaking in a pair of Omega SAHO's (60 hrs or so) with my Torii III and can say it is a gorgeous match as well.
I am extremely proud of owning an American made amp and speaker system that is the best I personally have ever heard.

JD
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